Why is a post request not being sent to guzzle 6?

Question

Web development

You need to send a post request from the Laravel application to a separate url. So that the receiving side receives it in $_POST['inputData']
I do this ($data is a json string):

$client = new Client();
$request = $client->post($url, NULL, ['insertData' => $data]);

However, $_POST is empty on the receiving side.
What am I doing wrong? There is nothing in the documentation about this, only on examples of get requests, which is not close to my case

Answer 1

$client->request('POST', '/post', [
    'form_params' => [
        'foo' => 'bar',
        'baz' => ['hi', 'there!']
    ]
])